Williams' drivers Valtteri Bottas and Felipe Massa finished third and fourth respectively in the Austrian Grand Prix on Sunday after a front-row lock-out in qualifying.

Claire Williams is confident her team is on the way back to being a major force in Formula One after a recent return to form.

Williams' drivers Valtteri Bottas and Felipe Massa finished third and fourth respectively in the Austrian Grand Prix on Sunday after a front-row lock-out in qualifying, giving the British outfit its best points return (33) from a single race since a new scoring system was introduced in 2010.

It was all very different last year when Williams, a team with nine Formula One constructors' championships and seven drivers' titles to its credit, could only manage just five points with a ninth-place finish confirming their worst-ever season.

That campaign came after several years of struggle for a team founded by Frank Williams, Claire's father, that has been a fixture on the Grand Prix circuit since 1977 and competed in more than 600 races.

But March saw Williams impress at pre-season testing in Bahrain, having brought on board the likes of Pat Symonds as chief technical officer, Rob Smedley as head of vehicle development and Jakob Andreasen as head of engineering operations.

Claire Williams, now deputy principal in a team where her father remains in overall charge, said it wasn't just a case of the newcomers transforming Williams' fortunes.

"It's been a combination of factors.

"We had a great team before those guys came in, but it was a case of augmenting that with more support at a senior level.

"Having Pat, Rob, Jakob and a number of other guys behind the scenes as well who we brought in, supporting the talent we have, has been a game-changer for us," added Williams, whose team last won a world title in 1997 courtesy of Jacques Villeneuve.

"It's all about momentum as well, and with team morale at a really high level now, it all goes to build to your position, and that is where we are as a team," she explained ahead of the team's 'home' British Grand Prix at Silverstone in central England on July 6.

And Williams insisted that, having shown they could could compete with the likes of pacesetters Mercedes, prospects for the team were bright.

"There is so much positive momentum. We have to embrace that, capitalise on it so we make the most of it for the rest of the season.

"Everyone believes this team can get back to the top, and you have to believe in that in order to do it."